Answer:
The efficiency is 0.33, or 33%.
Explanation:
From the thermodynamics equations, we know that the formula for the efficiency of a heat engine is:
Where η is the efficiency of the engine, Q_1 is the heat energy taken from the hot source and Q_2 is the heat energy given to the cold object. So, plugging the given values in the formula, we obtain:
This means that the efficiency of the heat engine is 0.33, or 33% (The efficiency of an engine is dimensionless).
Answer:
Power dissipated in resistor 532 ohm is 0.503 watt
Explanation:
We have given in first case resistance
Power dissipated in this resistance is
Power dissipated in the resistor is equal to
We have to find the power dissipated in the resistor is 1.30 watt
From the relation we can say that
So power dissipated in resistor 532 ohm is 0.503 watt
Answer:
The person should use a convex lens of power -0.625 D.
Explanation:
Given that, the far point of the person, with myopic eye, is 160 cm.
It means that the image of an object, which is at infinity, is formed at this point 160 cm distance away from the person's eye.
If the object is infinity, then the object distance, u = -.
Image distance, v = -160 cm.
u and v are taken to be negative because the object and the image of the object are on the side of the eye from where the light is coming.
Let the focal length of the lens which is to be used for the correction of this myopic eye be f, then using lens equation,
The negative focal length indicates that the lens should be convex.
The power of the lens is given by
So, the person should use a convex lens of power -0.625 D.